Beyonce, Coldplay and Bruno Mars will perform for an audience of more than 100 million as they take to the Super Bowl half-time stage.

British band Coldplay will make their Super Bowl debut on Sunday, while pop superstar Beyonce will return to the stage for the first time since 2013. Mars played a year later, in 2014.

Beyonce surprised many fans by releasing new single Formation on Saturday on Tidal, the streaming service she co-owns with husband Jay Z, among others.

Normally, a subscription to the service is required but the track is available to download for free.

A video set in New Orleans was also released on YouTube which depicts an area stricken by flooding, recalling the 2005 disaster caused by Hurricane Katrina.

It includes references to America's Black Lives Matter movement, which grew out of the 2014 shooting of 18-year-old Michael Brown in Ferguson, Missouri.

Graffiti reading "stop shooting us" is visible on a wall and a boy wearing a hooded top holds his hands in the air in a move evoking the "hands up, don't shoot!" slogan popularised at protests over the shooting.

The Super Bowl is the highlight of the American football calendar, and attracts some of the biggest names in music for the half-time entertainment show.

Previous performers include Katy Perry, Madonna, and the Rolling Stones.

An average of 114.4 million people watched Super Bowl in 2015, making the game the most watched in the history of US television.

Speaking at a press conference for the Super Bowl, which will see the Denver Broncos play the Carolina Panthers, Coldplay's Chris Martin said: "We love Beyonce's music and she's one of the greatest performers I've ever witnessed.

"The people from NFL came to us this year and wanted us to include the past, present and future ... the way we are honouring the past is to look at the people whose past half-time shows we really loved, and Beyonce's is right up with that."

Perry's performance of her hit Teenage Dream in 2015 sparked the "left shark" meme, with viewers bemused by one of the two backing dancers in shark outfits who appeared to have gone rogue.

Paying homage to that moment, Martin joked: "We've got left shark, middle shark, front shark, back shark, two right sharks and the reserve shark in case one of the first sharks has a problem."

He added: "No viewer at home will have any shark-based trauma."

Lady Gaga has been confirmed to sing the US national anthem before the game begins.

The Super Bowl will also include some of the world's most expensive and star-studded commercials, as brands make the most of the millions-strong audience.

British actress Dame Helen Mirren will feature in an advert for Budweiser, warning Americans not to be a "pillock" by drinking and driving.

Deadpool star Ryan Reynolds will appear in an advert for Hyundai's 2017 Elantra, while rapper Drake will be shown parodying his Hotline Bling video for T-Mobile.

Liam Neeson will be seen in a spot for LG's new OLED TVs and Aerosmith frontman Steven Tyler will plug Skittles.

The average 30-second Super Bowl spot commands as much as five million US dollars, according to Forbes magazine.